1. Field of the Invention
The present invention relates to an optical transmission system to perform optical transmission using a spatial multiplexing optical fiber as an optical transmission line for transmission of signal light.
2. Related Background Art
A multi-core optical fiber (MCF: Multi-Core optical Fiber) is an optical fiber in which a plurality of cores each capable of guiding light beam in a propagation mode are covered by a common cladding. A multi-mode optical fiber (MMF: Multi-Mode optical Fiber) is also called a few-mode optical fiber (FMF: Few-Mode optical Fiber) and can guide light beams in a plurality of propagation mode through one core. These optical fibers are generally called spatial multiplexing optical fibers.
An optical transmission system to perform optical transmission using a spatial multiplexing optical fiber as an optical transmission line for transmission of signal light can guide light in multiple propagation modes by the spatial multiplexing optical fiber. For this reason, it is able to transmit and receive a large volume of information when compared to the case where a single-mode optical fiber is used as an optical transmission line.
In the optical transmission system using the spatial multiplexing optical fiber as an optical transmission line, crosstalk (XT) between multiple propagation modes raises a problem. P. J. Winzer et al., ECOC 2011, paper Tu. 5. B. 7 (Non Patent Document 1) reports the effect of XT between propagation modes on transmission quality Q-factor in MCF.